1. In a network, the ratio (1– x/y), where: y is the number of cells that arrive in an interval at the ingress of the network; and x is the number of these y cells that leave at the egress of the network. [T1.627-1993] 2. In a network element, the ratio (1– x/y), where y is the umber of cells that arrive in an interval at the ingress of the network element; and x is the number of these y cells that leave at the egress of the network element. [T1.627-1993]